Encephaloduroarteriosynangiosis for hemorrhagic moyamoya disease: long-term outcome of a consecutive series of 95 adult patients from a single center.

Objective: The objective of this study was to investigate long-term outcomes after encephaloduroarteriosynangiosis (EDAS) for the treatment of hemorrhagic moyamoya disease (MMD) and identify the risk factors for recurrent hemorrhages.

Methods: The authors retrospectively reviewed 95 patients with hemorrhagic MMD who were treated with EDAS at 307th Hospital PLA. Clinical features, angiographic findings, and clinical outcomes were investigated. Rebleeding incidences were compared between anterior or posterior hemorrhagic sites. Kaplan-Meier survival analysis and Cox proportional hazards regression models were used to estimate rebleeding risks after EDAS.

Results: The average age at symptom onset was 37.1 years (range 20-54 years) for adult patients. The ratio of female to male patients was 1.16:1. In 61 of 95 hemorrhagic hemispheres (64.2%), the anterior choroidal artery (AChA) or posterior communicating artery (PCoA) was extremely dilated, with extensive branches beyond the choroidal fissure, which only occurred in 28 of 86 nonhemorrhagic hemispheres (32.6%). Fifty-seven incidences were classified as anterior hemorrhages and 38 as posterior. Sixteen of 95 patients (16.8%) suffered cerebral rebleeding after a median follow-up duration of 8.5 years. The annual rebleeding rate was 2.2% per person per year. The incidence rate was higher for the posterior group than for the anterior group, but this difference was not statistically significant (p > 0.05). Cox regression analysis revealed that the age of symptom onset (OR 1.075, 95% CI 1.008-1.147, p = 0.028) was a predictor of rebleeding strokes.

Conclusions: Through long-term follow up, EDAS proved beneficial for patients with hemorrhagic MMD. Dilation of the AChA-PCoA is associated with the initial hemorrhage of MMD, and rebleeding is age-related. Patients with hemorrhagic MMD should undergo follow-up over the course of their lives, even when neurological status is excellent.